(1) Suction pipe of sewage pump Each sewage pump should be set with a separate suction pipe, and strive to be short, in order to improve water conservancy conditions, reduce head loss, and reduce the possibility of impurities blocking the pipeline.
The design flow rate of the suction pipe is generally 1.0~1.5m/s, and the lower one should not be lower than 0.7m/s, so as to avoid precipitation in the pipe. When the suction pipe is very short, the flow rate can be increased to 2.0~2.5m/s. In order to facilitate the removal of the stored air in the suction pipe, the horizontal part of the suction pipe should be slightly elevated along the direction of the water flow, and the pipe slope can be 0.005. When the connection between the suction pipe and the water pump needs to be tapered, an eccentric head should be used. The inlet of the suction pipe should be equipped with a bell mouth whose diameter is 1.3 to 1.5 times the diameter of the suction pipe. The bell mouth is installed in the sump of the sump.
For self-priming pumps, valves should be installed on the suction pipes for maintenance. If the pump is not self-priming, it should use a vacuum pump or a water ejector to start water, and it is not allowed to set a bottom valve on the suction pipe, because the bottom valve is easy to block in the sewage, which affects the starting of the pump, and increases the head loss and electricity. consumption.
(2) The water outlet pipe of the sewage pump The flow rate of the water outlet pipe of the sewage pump is generally not less than 1.5m/s. When two or more pumps share one water outlet pipe and only one pump works, the flow rate shall not be less than 0.7m/s. s to avoid deposits in the tube. When the water outlet pipe of the pump is connected to the water outlet main pipe (connecting pipe), it must not be connected from the bottom of the main pipe, so as to avoid the formation of silt in the water outlet pipe of the pump when the pump stops running.
When two or more pumps share one outlet pipe, the outlet pipe of each pump should be equipped with a valve, and a check valve should be set between the valve and the water pump; if the water pump adopts a separate outlet pipe, and it is free flow In general, no check valve is required, and all valves should be installed in the horizontal section as much as possible to prevent dirt from depositing on the valve disc.
The laying of pipelines in sewage pumping stations is generally exposed. The suction pipe is often set on the ground, and the outlet pipe is usually installed overhead because of the deep pump room, usually along the wall on the bracket. The arrangement of the pipelines shall not interfere with the traffic and maintenance work in the pumping station. It is not allowed to install the pipelines above the electrical equipment, and shall not interfere with the traffic in the station, the hoisting and maintenance of the equipment, and the suction pipes and outlet pipes of the ground sewage pumps at the passing places. Pay attention to the points of the sewage pumps The distance between the suction pipe and the water outlet pipe should not be less than 2.0m from the bottom of the pipe, and the pipe should be stable. In order to facilitate installation and disassembly, the pipes in the pump station generally use flange interfaces. Corresponding anti-corrosion measures should be taken for pipes and valves.